Gun training mechanism



June 2, 1953 K. CLARK 2,640,395

GUN TRAINING MECHANISM Filed May 9, 1945 6 Sheets-Sheet l INVENTOR. Kwomty UML BY .wpfauh June 2, 1953 K. CLARK 2,640,395

GUN TRAINING MECHANISM Filed May 9. 1945 e sheets-sheet 2 fi Z u A) June 2, 1953 K. CLARK 2,640,395

GUN TRAINING MECHANISM Filed May 9, 1945 6 Sheets-Sheet 3 Kewl u Chu-k J. my L June 2, 1953 K. CLARK GUN TRAINING MECHANISM 6 Sheets-Sheet 4 Filed May 9, 1945 June 2, 1953 Filed May 9, 1945 K. CLARK GUN TRAINING MECHANISM 6 Sheets-Sheet 5 nlonoooooo INVENTOR. Kandel CUAYK BY o- @MJL 319'* "June 2, 1953 Filed May 9, 1945 K. CLARK GUN TRAINING MECHANISN 6 Sheets-Sheet 6 l INV ENT OR.

Patented June 2, 1953 UNITED STATES PATENT OFFICE GUN TRAINING MECHANISM Kendall Clark, Oakwood, Ohio `Application May 9, 1945, Serial No. 592,765

(c1. ssa- 41) 9 Claims.

This invention relates to gun turrets and includes a method of and apparatus for training gunners.

It is an object of my invention to provide a training turret having a compensating gun sight and a moving target together with a means for simulating the firing of the gun and recording the number of simulated shots fired as well as the number of simulated shots which would have hit the target.

It is another object of my invention to provide an improved and more responsive mechanism for controlling the movement of a gun which will reduce hunting and which is applicable both to guns for training purposes and to guns used in actual combat.

These objects are attained by providing a turret similar to the turret used for actual combat having compensating gun sight and gun simulating means with a firing control together with a movable target which may be automatically or manually controlled and provided with a compensating means in order to compute the proper direction of the gun upon the target. An improved form of continuously operating drive means to control the movement of the gun in .vertical and horizontal directions is provided with an initially effective manually operated accelerating device to reduce hunting.

Further objects and advantages of the present invention will be apparent from the following description, reference being -had to the accompanying drawings wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. l is a view in elevation of a training turret and target control embodying one form of my invention;

Fig. 2 is a top View of the turret shown in Fig. 1;

Fig. 3 is a fragmentary view of the turret with the target elevated to a 30 angle and the sight elevated to a 15 angle;

Fig. 4 is a view in elevation of the gun moving drive unit which is applicable both to the training turret and to an actual combat turret;

Fig. 5 is a side view of the drive unit shown in Fig. 4 together with a portion of the turret track, taken on the line 5 5 of Fig. 2;

Fig. 6 is a small view of the speed adjusting pulley drive shown in Figs. 4 and 5 illustrating the position of the drive for movement of the gun in one direction;

Fig. 7 is a small view of the pulley drive positioned for holding the gun stationary;

Fig. 8 isla small view of the pulley drive posi- 2 tioned for movement of the gun in the opposite direction;

Fig. 9 is a horizontal sec-tional view of the drive unit shown in Fig. 4 taken along 9-9a-9b of Fig. 10;

Fig. l0 isa sectional View taken along the lines iii-I0 of Fig. 9;

Fig. 11 is a view of a machine gun which may be used in pairs upon the turret shown in Fig. 1 when used in actual combat.

Fig. 12 is a front view of the compensating means for compensating for the speed of movement of a target in order to accurately score the gunner;

Fig. 13 is a sectional view taken along the line l3-l3 of Fig. 12;

Fig. 14 is a sectional View taken along the lines `ill- M of Fig. 12;

Fig. l5 is a rear view of the gun moving and ring control; and

Fig. 16 is a wiring diagram of the target control system, the target compensating system and the scoring system.

Referring now to the drawings and more particularly to Figs. l to 3 there is shown a square angle iron base 2l from the corners of which four or more struts 23 extend upwardly to support two stationary rings 25 and 2l of channel iron, the webs of which are placed back to back with a space in between as shown in Figs. 2 and 5. The channel iron rings 25 and 2l, which may be made integral in the form of an I section, form a rigid stationary support in the form of two circular tracks or rings. The outer stationary track 25 is for the support of the target-carrying mecha- -nism to be hereinafter described, and the inner stationary ring 2l is for the support of the turret or gun-carrying mechanism.

Target mechanism Upon the outside of the stationary outer ring 25 there is rotatably mounted a movable ring 29 formed of channel iron which is supported in the channel of the stationary ring 25 by the rollers 3l which are rotatably mounted upon the stub shafts 33 held by the flanged supports 35 which are fastened to the web of the channel or movable ring 29.

The movable ring 29 is provided with a pair of brackets 31 (Figs. 1 to 3) each provided with a bearing for supporting a pivot pin 39 providing a pivotal connection with the U-shaped target support loop 4l which overlaps substantially one-half the circumference of the ring 29. The target i3 which may have the outline of an aeroplane is provided at the middle point of the support loop 4|. The support loop 4| is provided with a pair of counterweights l5 to 'correct its unbalance. The target support loop 4| is provided wth a sector gear t9 driven by an electric motor 5i through a pinion gear 53. The motor 5|, which is supported by the bracket 52 fastened to the movable ring 2S, has directly connected to it a small generator 55 the purpose of which will be explained hereafter. The motor 5| drives a pinion 53 in engagement with the sector gear |59 to elevate or lower the target t3. In order to move the target horizontally, a second motor 51 is provided with a gear reduction extending to a rubber tired roller 59 in driving engagement with the lower face of the movable ring 2S. This motor 51 is supported by the bracket 6| fastened to the stationary ring 25. The motor 51 is likewise coupled to a small generator d3 for a purpose to be explained hereafter.

The motors 5| and. 51 are controlled manually by the remote target control 65 (Fig. 1) provided With a single vertical and lateral control 51 in the form of a control stick which projects upwardly from the control box G9 which is provided -with a universal type lsupport (not shown) at the lower end of the stick. The target control 55 is `connected by suitable ilexible conductors in the flexible casing 1| with the motors 5| and 51 and by two flexible conductors in the flexible casing 13 with a suitable source of power. The operation of the control 65 will be explained hereafter in connection with Fig. 16.

The turret housing Within the stationary inner ring 21 is a movable ring 15 of channel iron (Figs. 2 and 5) which forms the main frame of the turret. This movable ring l5 is rotatably supported within the stationary ring 21 by the rollers |2|3 which are vrotatably mounted upon the stub shafts |22 supported by the flanged hubs l2@ mounted upon The gun mount The movable ring 15 is provided with a pair of brackets 9| which pivotally support a gun yoke 93. Supported upon this gun yoke are a pair of simulatedguns 95 which may be of any suitable type when the turret is used for trainlng purposes. When the turret is used for actual combat or ring purposes, the pair of simulated guns are replaced by actual machine guns of any suitable type, an example of which is shown in Fig. ll. In order to elevate the gun yoke 93 and `the-guns 95 there are pivotally connected to the .opposite sides of the yoke 93 the links 91 which connect to a pair of sector gears 99 fastened to a cross rod |62 rotatably supported by the brackets H14 upon the movable ring 15. -gears 9S mesh with pinions |65 upon opposite kends of the shaft |06 (Fig. 2) which extends in opposite directions from the turret drive unit |58.

The sector The turret drive unit |08- is supported by the brackets It carried by the movable ring 15.

In order to rotate the turret, the turret drive unit IM is provided with a hub l l2, having a bearing H6 (Fig. 9) in its outer end. Protruding from this hub is a shaft l i6 which carries a pinion H8 which is in driving enga-gement with ring gear |59 upon the bottom face of the stationary ring 21, as best shown in Fig. 5. The rotation of this pinion |58 turns the ring and the entire turret relative to the stationary ring 2l. instead of the pinion H8, a rubber tired roller may be used in direct engagement with the bottom face of the stationary ring 21. The ring gear lill is then omitted.

Gun control Referring to Figs. l, 2, 3 and l5, the gun and turret control is provided with a pair of handles |26 to be clasped by the gunner for moving the gun both vertically and horizontally. One of the handles is provided'with trigger l2|2 for controlling the firing of the guns or any simulations thereof. As is best shown in Fig. i5,the handles S26 are connected together by a hollow boxshaped handle bar |30 which may contain compui-,ing instruments for the sight 548, if desired. This handle bar is supported by a universal joint connection |32 upon a bracket itt extending from the vertical supports 83. The handle bar. |39 is connected in its middle rear by elevation control rod EBS to the lever |38 upon the end of the shaft |555 of the turret drive unit |03 as shown in Figs. 3, el, and 5. 'This controls the gun elevating drive provided by the turret drive unit |58 through the shaft idd and the pinions m5 which mesh with the sector gears 93 carrying the links 91 which connect with the gun yoke 83. At one side, the handle bar |30 is connected by the azimuth control rod |42 with the lever itt provided on the inner end of a shaft Mld 4 and 9) in the control portion of the turret drive unit i558. The shaft |45 controls the rotation of the pinion l I8 to rotate the turret.

The mechanism of the turret drive unit Referring now moreparticularly to, Figs. l to 10 inclusive, it will be seen that the shaft itil is loca-ted in axial alignment With the shaft MS directly beneath and parallel to the shaft |06 as shown in Fig. 5. This shaft Mil protrudes from the outer end of the drive unit |08 and is provided with an arm |48 carrying an idler pulley |58 which is in contact with a V-belt |52. This V-belt |52 extends around a xed pitch pulley |54 nxed to the shaft |56 protruding from the one end of the drive unit |08 and a spring pressed variable pitch pulley |58 xed to one end of the drivel shaft |53 of the double ended electric motor supported by the bracket |62 of the tur- 'ret drive unit |08. This end of the motor shaft |59 also is provided with the xed pitch pulley |64 for driving' by meansv of the V-belt |65 a fixed pitch V-belt pulley |68 o1' twice the pitch diameter of the pulley |54. This side of the turret drive unit is employed to control the elevation or zenith movement of the gun.

Upon the opposite side of the turret drive unit H18, which controls the horizontal or azimuth movement of the gun, the shaft |46 is` provided at its outer end with an arm |10 carrying an idler pulley |12 which is maintained in contact with the V-belt |1l| extending around the fixed pitch pulley |16 and the variable pitch pulley |18 fixed to the end of the drive shaft |59 of the double ended electric motor |60. This pulley |18 is provided vvith one flange which is fixed to the upon the motor shaft. lresiliently urged toward the fixed flange |80 by l ret. 20| and the sleeve of the carriage 2 I5 are all rotatably mounted on the shaft |92.

5 end of the moto-r shaft .and a seco-nd flange |82 which is slidably but non-rotatably mounted This second flange |82 is the compression spring |84 located between the flange |82 and a smaller pulley |86 which is fastened to the motor shaft |59. The pulleys |58 i' and |10 are identical with the exception that the shaft endsand pulleys are reversed in posileys |54 and |16, as illustrated in Fig. 6, to a ratio wherein the pitch diameter of the pulleys |58 and |18 is one and one fourth times the pitch diameter o-f the fixed pitch pulleys |54 and |16, as illustrated in Fig. 8. This range of ratio may be increased or diminished as required in order to provide a. greater or lesser range of speed variation.

The pulley |16 is xed to the shaft |92 to which is keyed a bevel gear I9l| meshing with a set of differential gears |96 which are freely ro-tatably mounted upon the differential hub |38, The differential hub |98 extends in the form of a sleeve concentricallyl mounted upon and rotatable independently of the shaft |92 with the pulley |00 iixed upon its outer end. The foregoing elements together with the bevel gear 209 constitute the iirst azimuth planetary system. The pulley |50 is similarly connected through the shaft |56 to a beveled gear 203 which meshes with the freely rotatable differential gears 205 carried by the differential hub 201 which, similarly is rotatably mounted on shaft |56 and carries a pulley |68, upon its outer end. The foregoing elements together with the bevel gear 22| constitute the first zenith planetary system.

The diiferential gears |96 mesh with a second beveled gear 209 having a spur gear 20| mounted directly thereon which forms the sun gear of a second azimuth planetary system which includes the planet gears 2| enmeshed with the sun gear 20| and ring gear 2|3.

The planet gears 2| I are rotatably mounted upon a carriage 2 I5 provided with a sleeve extending to carry the bevel gear f 2 I1 which meshes with a bevel gear 2 I9 provided at the inner end of the azimuth shaft ||6 which through the pinion or roller H rotates the tur- The second beveled gear 209, the spur gear On the other side `of the unit used for elevating the guns, the

l differential gears 205 mesh with thebevel gear L 22| which has coupled directly to it the second zenith planetary system which includes a sun gear 223 meshed with the pla-.net gears 225 which in turn mesh with an internally toothed ring gear 221. The planet gears are carried by a carriage `220 which in turn carries a helical gear 23| connected through an idler gear 233 with a helical gear 235 xed to the shaft |06 which extends in opposite directions and is provided with the zenith or gun elevating gears at its opposite ends of the turret drive unit |06, as best shown in Fig. 2. The bevel gear 22 i, the sun gear 223 and the sleeve of the carriage 229 are all rotatably mounted on the shaft |56.

With this construction, the turret rotatmg or 1 azimuth drive section contains two plenetary or Il l) epicyclic gear trains and likewise the gun elevating or zenith drive section contains two plenetary or epicyclic gear trains. The first epicyclic gear train of each section is that which includes the differential gears |96 for the azimuth drive and the differential gears 205 for the zenith drive. It will be understood that by this differential drive arrangement if the pulleys |68 and |54 turn at the same angular speed the differential is, in effect, locked and the bevel gear 22| turns at the same speed as the pulleys |68 and |54. But if the pulley |54 turns at twice the angular speed of the pulley |68 as in Fig. 7 then the bevel gear 22| will remain stations ry and there is no movement of the zenith driving gear |05. This is true because the differential gears'205 rotate'in the opposite direction with respect to the gear 203 and therefore neutralize under these conditions the rotation of the gear 203.

When as in Fig. 6 the pulley |54 rotates at a speed between one and two times the speed of the pulley |68 the bevel gear 22| will be given a rotational movement in the same direction as the pulleys but at a reduced speed which approaches zero as the pulleys approach a two to one angular speed ratio. When as in Fig. 8 the pulley |54 rotates more than twice as fast as the pulley |68 the bevel gear 22| will turn in the opposite direction at a speed which will increase as the ratio increases above two to one. This type of drive is especially valuable for moving a gun both in azimuth and in zenith since it is possible to keep the drive motor and gearing rotating continuously so that it is instantly avail-able for moving the gun. It has the further advantage that the motor and connected gearing have sufficient rotational inertia so as to make the drive mechanlsm immediately responsive to the gunners control.

The second planetary or epicyclic gear train of the azimuth as well as the zenith sections has two functions. One function is to provide speed reduction and the other function is to reduce hunting in training the gun sight upon the target.

When an operator endeavors to train a sight upon a moving target such as an aeroplane he must first speed up the gun moving mechanism lat a more rapid rate than the moving target in order to catch up with the moving target. As the moving target comes within the field o-f sight it is necessary to slow down the gun moving mechanism until it is equal to the speed of the moving target. This almost inevitably causes the over-running of the target in the sight several times. In order to reduce this difliculty I provide means whereby, when the control for the driving mechanism is moved to start movement of the gun, an additional accelerating force is superimposed upon the turret drive unit. r)This provides an especially rapid start for the movement of the gun which quickly slows down so that it follows the normal gun movement requirements of rapidly catching up with the target. This effect also pro-vides a quick negative acceleration or deceleration for slowing down to the speed of the target when the target comes within the field of sight. This aids in reducing the amount and frequency of over-running the target. This positive and negative acceleration effect is referred to as kick in the claims.

The mechanism for accomplishing this purpose is illustrated in Figs. 9 and 10. `This is accomplished by fixing a forked arm 24| to the azimuth control shaft |46 and a similar' forked arm 243 to the zenith control shaft |40. The forked arm 2M is provided with a slot 245 which engages a pin 241 protruding from the ring gear 2I3. The

ring gear 2id is thus held stationary as long as the azimuth control shaft MS is held stationary. In the second azimuth planetary system the three gear elements 2i I and 20| and 2 I3 mutually react upon one another but when the ring gear M3 is held stationary it takes the reaction, and the planet gears 2 I I then rotate in directl proportion to the rotation of the sun gear 2M. The ring gear 2I3 is therefore sometimes referred to as a normally stationary reactor ele-ment. As is shown best in Fig. 10 the forked arm 2M has a. movement of nearly 90 and is capable of moving the ring gear 213 about 30 in either direction from the midpoint of the arm 2M. This initial movement of the normally stationary ring gear 2 I 3 provides .an added rotation of the planet gear Z I I and the bevel gears 2 Il and ZIS and the turret drive gear I i3 which provides the initial burst of speed which is very desirable in moving the gun when itis being trained upon the target. Thus the` movement of the ring gear 2 I3 provides a movement of the plane-t gears 2 I I even though the sun gear Ztl be stationary. If the sun gear 25H should be rotating at one speed to normally drive the planet gears 2H at a second speed in direct proportion thereto, the movement of the ring gear 2 I3 will either increase or decrease the speed of the planet gears 2H from that second speed, depending upon whether the ring gear 2 I3 is rotated in the same or opposite direction as the rotation of the sun gear MI. For example, the ring gear 2 i3 is rotated in the same direction as the sun gear lidi when it is desired to speed up I the movement of the turret or the gun in any given direction while the ring gear 2 i3 is rotated in the direction opposite to the rotation of the. sun gear when the movement is slowed down. By this arrangement whenever the handle bar control is moved initially to start the operation of the azimuth drive section, the ring gear 2I3 is` moved in the direction of the desired movement an amount depending upon and roughly prop-ortioned to the speed that the operator desired from the azimuth drive section. The corresponding mechanism for the zenith drive section is not shown but the forked arm and the cooperating pin on the ring gear 221 are identical construction and operate in the same manner as described for the arm 24H and the pin 2M and the ring gear 2I3.

Wiring diagram-target moving portion Referring now to Fig. 16, there is shown the movable contact arm 25I which is controlled by the fore and aft movement of the control 6l (Fig. l) to lower or raise the target in its zenith movement, while the movable Contact arm 253 is controlled by the lateral or left and right movement ci" the control 5"! to control the azimuth movement oi the target to left and right respectively. The arm 25H taps a potentiometer coil 255 while the arm 253 taps the potentiometer coil 25'?. rllhese coils 255 and 251 are connected in parallel electric circuits across the direct current supply conductors 259 and 26I provided in the casing 'i3 (see Fig-1). The contact arm 251 is connected by the conductor 263 to the stationary conductor ring 265 mounted on Xed ring-25 (see Fig. 5) which is always contacted by the contact 267y supported by the movable target carrying ring 29. This contact 25? is connected by the conductor 269 to the commutator brush 2'II of a direct current motor 5I which moves the target 8 G3 in a vertical direction. The other commutatcr brush 2l3 is connected by the conductor 215 to the movable contact 27'! of the potentiometer coil E79. This potentiometer coil 219 is connected across the supply conductors.

The supply conductors tti and 25S are connected tc the stationary conductor rings 2.3i and 251% upon which ride the wiping contacts i395 and 228i provided upon the movable target carrying ring Sie. These contacts 285 and itl connect to the transmitting conductors 28o and ZM which connect to the electrical devices on the turret. The potentiometer coil El@ is connected at one end through the conductors 293 and 295 to the transmission conductor 29E and at the other end through the conductor 2.9i to the transmission conductor tilt. The eld coils 29d of the electric motor 5I are likewise connected by the conductors 362 and Bte across the transmission conductors 289 and 29E.

The motor 5i is provided With a shaft extension 'containing a worm Stil in operating engagement with the Worm gear 3&8 which drives the movable contact arm 2H in such a direction that when current now-s through the commutator of the electric motor Sil, the movable contact arm will be moved until it reaches a position where the current through the commutator will be zero. In eiect, the potentiometer coil 255 lforms the two resistances forming one branch of a Vlheatstone bridge circuit While the potentiometer coil 2id forms the two resistances of the other branch of the Wheatstone bridge circuit. The proportioning of the two resistances is provided by the movable contact arms 25I and 2TH which are connected through the brushes 2H and lll@ ci the electric motor 5l to iorin thn bridge of the Wheatstone bridge circuit in which the motor 5I takes the place of the lconventional galvanometer.

By this arrangement, when the control 6'! moves the movable arm 2li!- to any desired position, the motor 5! will rotate to elevate the target f3.3 (Figs. 2 and 3) through the gear 'i3 and the sector gear i9 until the movable contact arm ill' moves to a point where the current through this circuit becomes zero.

The azimuth target control is similar to the zenith target control. The movable contact arm 253 is connected by the conductor :lill to the stationary conductor ring Zilli which is contacted hy the wiping contact SI5 connected by the conductor 3 it to the brush 32S of the azimuth drive motor 5l which as its other brush 322 is connected by the conductor 32o to the movable contact arm 326. The movable contact arm Bilt makes contact with the potentiometer coil 32d. The potentiometer coil S28 as well as the field coil 330 of the motor 5l are connected in parallel electric circuit relationship across the transmission conductors 289 and 29 i. As in the zenith target control, the movement of the movable contact 253 causes the motor 5l `to move `the movable contact arm 325 and the target supporting loop tI to a position wherein the current through this circuit' becomes a zero. In this way the target i-s moved in azimuth and zenith, that is, horizontally and vertically in accordance with the movement of the control '5l which controls the position of `the contact arms 25| and 253.

Shot and hit computation system.

in order to count the number of shots, the gunner presses the trigger 28 which closes switch 328. The switch 32B is connected through the conductor 329 and the wiping contact 330 to the contact ring 28| which connects to the supply conductor 259. The switch 328 connects to the stationary. contact 332 of a pulsator or interruptor which includes an electromagnet coil 336 and an armature 334 adapted to make contact with the contact 332 when retracted from the coil 336. The coil 336 is connected electrically to the armature and -to the conductor 338 which connects through the wiping contact 348 with the stationary ring 283 which connects tothe supply conductor 26|.

i By this arrangement when the switch 328 is closed the pulsator repeatedly opens and closes the circuit. This is done by reason of the fact that when the armature 334 is in engagement with the contact 332, current will flow through the electromagnet coil 336 and attract the arma ture 334 to open the circuit. The opening of the circuit will deenergize -the coil 336 thereby allowing gravity or a spring t return the armature 334 in contact with the contact 332. This is so adjusted that a number of circuit interruptions substantially equal the firing rate of the type of gun to be used with this style of target. The interruptions corresponding to the shots which would be fired are counted upon a meter 342 which is connected in electric parallel circuit relationship with the electromagnet coil 336.

The hit computation system A simple addition to this circuit computes the number of hits the gunner makes upon the target 43. This is provided by a switch 344 which is connected in the circuit' which is arranged in parallel with the meter 342 and the electromagnet 336. This switch is so operated that it is closed whenever the gunner properly trains the sight' upon the target 43 as will hereafter be explained. This switch 344 controls the flow of current through this circuit which includes a second meter 346 which counts the impulses of current which flow through this parallel circuit when the switch 344 is closed. With this arrangement the number o shots can readily be determined by inspection o-f the meter 342 and the number of hits by inspection of the meter 346. From this, the percentage of hits relative to the number of shots can readily be determined. kThis provides the most important element in determining the skill of the gunner undergoing training.

The operating means for the switch 344 is more complicated. The gunner 81 is provided with a compensating gun sight 348 which may be a standard aircraft gun sight or one for example such as is shown in the Paulus et al. Patent 1,937,517. Such a sight will advance the gun 95. a proper amount ahead of the target viewed through the sight in order to compensate for the speed of the target as well as the trajectory of the bullets and shells. This is provided for by the computer box 356 which is mounted upon top of a turret drive unit |68 and is driven from the zenith drive through the helical gear 332 on the shaft 334 and from the azimuth drive by the helical gears 356 and 358 and the shaft 366. This computer box controls the sight 348 to provide the proper lead for the gun in advance or the sight upon the target.

The necessity of providing a lead for the gun in advance of the sight for a training turret of this type may be questioned. However, this is desirable in order to keep the gunnery trainee familiar in training in directing compensated sights upon atarget Vand experiencing the lead that such a sight provides for the guns. Inasmuch asa lead is provided for the gun and the entire turret in advance of the sight it is also necessary to compensate the counting mechanism to correct for the speed of the target. The switch mechanism 344 therefore must have compensation for the speed of the target.

The switch 344 proper is carried in a case at the end of an arm 362 (see Fig. 2) extending from the gun yoke 93. Thus this arm moves in accordance with the movement of the gun 95. The switch 344 has an operating cam 364 projecting from it. When depressed this cam closes the switch 344. In order to close the switch 344, I

rovide a cam 366 which is mounted upon compensating mechanism generally indicated by the reference character 368 and shown in detail in Figs. 12, 13, it and 16. This compensating mechanism includes a bracket 316 which is fastened to the target loop 4| provided with a post 312 for this purpose. The bracket 310 carries a horizontal or azimuth compensating mechanism which includes an electric motor 316 directly connected to a screw 318 which is in threaded engagement with a slide 380. This slide 380 is slidably mounted upon the rods 382 which have their end supports 384 providing the bearing supports for the screw 318. This structure provides the azimuth or horizontal compensation.

The zenith or vertical compensation is provided by the electric motor 386 which rotates the screw 388 which is threaded through the vertical slide 399 Carrying the cam 366. The slide 390 is mounted upon the rods 392 which terminate in the end support 394, one of which supports the motor 386. In addition to this mechanism, a potentiometer coil 396 (see Figs. 14 and 16) is carried between the bracket 382 and is contacted by the movable contact 398 xed to the slide 386. Also a potentiometer coil 48| is carried between the bracket 388 and is contacted by the movable contact 433 carried by the slide 39D.

As is best shown in the Wiring diagram, Fig. 16, the ends of the potentiometer coils 396 and 48| are connected across the transmission conductors 289 and 29|. The middle point of the coil 396 is connected by a conductor 405 to the commutator brush 481 of the generator 63 which is coupled directly to the drive motor 51. The other commutator brush 469 is connected by conductor 4|| with the coil 4|3 of a polarized relay 4|5. This polarized relay 4|5 has an armature or conta-ct member 4|1 which is connected at all times by conductor 4|3 to the transmission conductor 288. The construction of this relay 4| 5 is such that when no current flows through the coil 4|3 then the armature 4|1 will be at its middle point and not be connected in a circuit. Whenever a current flows through the coil 4|3 the armature 4| 'E acting as a reversing switch will make contact either with the conductor 42| or the conductor 423 depending upon the direction of current flow. The conductor 42| connects to one set 425 of field windings of the reversible motor 316 and the conductor 423 connects to the other set 421 of the i'leld windings which, when energized, cause the motor 316 to rotate in the opposite direction.

There is a predetermined voltage drop however through the potentiometer coil 396 at all times since it is connected across the transmission conductors 289 and 29|. When the horizontal or azimuth drive motor 51 is operated in accordance with the movement of the target control, the generator will generate a current in proportion to eleziofeee 'ed ci increment of the motor which is ribving the target te horizontally. This energizes the polarized relay H5 to make Contact with eith i" he conductor 1452i or 1323. This causes the operation 'ci the motor Bit in one direction or the other. The screw Sie is threaded in such a manner that the slide Stil will carry the movable contfact iin'd'er such conditions to the point where the voltage 'drop between the conductor M55 and tli'e contact 3&8 isyedual to the voltage generated DS the@'gene'rator 53 'so that no current will flow throghythe polarized relay a i5. This arrangement will cause the slide 336 to follow the speed o; the generator and to compensatev for the speed of the tai et in the horizontal direction.

sirnl ar arrangement is provided for the potentiometer coil dei, movable contact Sil and the l"zenith compensating motor 33E. The middie point f 'the potentiometer con les is, contar critici as; promesa with a movable ecntact connecteddirectly to the rnovalole con- 32fifwhi'chis rotated by the azimuth vtarget y y 'T' The coil of this forward-backward control del is connected bythe conductor 33 t9 tile commutare crush 'ne of the generator 5,5, weich is incvedty me 'zenith drive motor el. The other brush im or this generator is connected by the conductor 'i339 with theelectroiifalene pffar lay is also one which disconnects tle fclrcults when deen'ergized but when energreed makes contact with either the .conductor @l ier A'cCiriellicthr 'The 'conductor lill vconrre-cts to/diie ser 'eel of the nele windings while theccrrocetor "ate connects to the other ser its oithe hield windings causing "the rotation of lthe finster` set in opposite direction depending pon 'the position of the polarized `relay 'Zi-53. 'Qfl'eferd of the coil 'off the forward-backward control er: isjconnec'tee by 'a conductor to the` 'conductor tee. The forward-backward control/ii fivaries the flow of current 'provided by generator "55 'in vaccordance with the disection crftrretrret with resp-ect to the une of flight pf the airl'ne 'upon 'which it is mounted.

The p'r or 'me ver-tical 'drive motor tu causes the 'generator 'e5 ,to "generate `a current irppo'fsition to the vertical speed of the target 4'3. This fcn'rfrnt fis lcompensated for rdirection bythebackwameforward Compensator rise cdntrol 'd by the rotational Aposition of the turt. 'llriec'urrent 4is rused to 'operate the polarized lelay litt which in turn controls the operation of or 3BE in either direction. y The vertical screw Seil lis so threaded that when the motor i' 36 'ftuis "i-twill continue vto turn and move the ntact @il in such a direction that the voltage drop :between the conductor A29 rand jiiiovable [contact fio-3 equals the voltage generated Lby :the "zenith target generator 55 'as 6mp ated for the con'lpensator e36. The th A'targetgener'ator it and the 'azimuth target g crater 6 3 have 'such a generating rate that th above *describedcircuit and mechanism will nieve the "-can i335 vto vthe proper `position both vertically 'and Ihoriaontally to compensate `-for the vertical and horizontal speed ofthe target so'ftl'i'atwlden the-'sight Slis is properly vtrained upon the larget E53, the cam '385 will engage the V"cam ist@ of the switch mechanism 'en to close the vv'switch lf the trigger 28 *should happen to vbe depressed toclose the switch 328 the'n both 'mechanisms -342 and 3516 would count each liin-pulse in the circuit controlled 'by the d by cqndiictor c2c to a forward'-b'acir` f1.

t cil del of 'the 'polarized r'elayffi. This 12 pulsator sat. '1f the trigger |23 is not de pressed, the pulsato1" 38% will not operate to provide impulses. If the 'cam switch 3M` is not closed only the shot meter 342 will be op;-

erated. y y

While I have described the disclosure as ape plied principally to a gunnery trainer it is obvious that many features can be applied directly to a gun turret or gun moving mechanism ine cluding particularly the drive mechanism and the compensating 'drive therefrom.

While the form of embodiment of the invention as herein disclosed constitutes a preierred form, it is to be understood that other forms might be adopted, as may come within the Scope of the claims whichl follow.

What is claimed is as follows:

1. In combination, a gun, an yepicyclic train for moving the gun, said epicyclic train includ ing three movable elements, means connecting a iir'st of said movable elementsjan-d the gun, means for `driving one 'of the other two elements during the use of the "gun, mea-ns vfor varying the relative speed of driving said one of the other two movable 'elements to -causethe gun to move, a control means for `controlling the speed of driving said one of the two flee ments, and means connected to aindgoperab'le only during and in response to every change in position of the control means yror Amoving the second of the two other elements of the epicyclic train in a direction to provide `a :positive or negative accelerating kick roi the gun in `the same direction as the change in speed of driving said one of the two 'elements resulting from the change in position of the control means.

2. In combination, a gun, afguninovin'g meehanism, a power drive, an e'p'icyclic *train having three movable elements, -Inean's connecting fone of said elements to the power `drive, .means connecting a. second of said elements and Saidfgun moving mechanism, a control means for v"said power drive, and means connected to and operable only during and in response to every change in position of the control'rneansformving the third element or" :the 'epicyclic train 'in a direction to provide a positive or negative accelerating kick of the fgun rmoving mechanism in the saine direction as the change Ein speed of the power drive vresulting from thechangein position of the control means.

3. In combination, a work member, an epicyclic train having three movable elements, a power delivery'means connectedto the Erst-mov'- able element of the train, a movement transmitting means connecting asec'ondof the movable elements of the Itrainlto the work menber for'operating the work memben'control means for changing the speed of said power delivery means to provide a proportionate change `in speed of the wor-l; meinbelg and 1Umeans connected'to and operable only ""durin'gan'd infresponse to eveiychange in position o'f-said'c'onitrol Ameans for positively moving :said third movable element of said epicyclic vtrain in `da direction `to provide a positive `or -negative accelerating kick. of the work member vin th'esame direction las the-change in speedof `Athe power delivery means resulting fromthechangeinfposition ci the controlmeans.

4. lin lcombination,'a work inernbenranl picylic train having three 'movableelements, v-a power delivery 'means connected to the first movable element VYof the train, fa Vmovel'rrient transmitting means connecting *a ``secondi`of i the movable fielements of the train to the work member for moving the work member, control means having an operating element for changing the speed of said power delivery means to provide a change in speed of the work member proportionate to the change in speed of the power delivery means, and means connected to and operable only during and in response to every change in position of said operating element for positively moving said third movable element of said epicyclic train in a direction to provide a positive or negative accelerating kick of the work member in the same direction as the change in speed of the power delivery means resulting from the change in position of the operating element.

5. In combination, a work member, an epicyclic train having three movable elements, a power delivery means connected to the irst movable element of the train, a movement transmitting means connecting a second of the movable elements o the train to the work member for moving the work member, control means having a movable operating shaft means for varying substantially in accordance with its movement the speed of said power delivery means, and mechanical operating means mechanically connecting said shaft means with the third element of said epicyclic train for positively moving only during and in response to every movement of said shaft means the third element of said epicyclic train to provide an accelerating kick of the work member in accordance with the change in speed of the power delivery means.

6. In,` combination, a power source, a work machine, a transmission train connecting the power source and the machine for transmitting power to the machine, said transmissi-on train including three mutually reacting elements, one of said three elements being a normally stationary element, a control means for changing the speed of the power source to provide a proportionate change in speed through the transmission train t the work machine, and means connected to and operable only during and in response to every change in position of the control means for positively moving said normally stationary element in a direction to provide an accelerating kick of the work machine in the same direction as the change in speed of the power source resulting from the change in position of the control means.

7. In a turret, a power source, a work machine, a power transmission train operatively connecting said power source and said work machine for transmitting power from the source to the machine, said train including an initial element connected to the power source and a transmitting element connected between the initial element and the work machine, a normally stationary reactor element against which said transmitting element reacts while transmitting power, control means for changing the speed of said power source to proportionately change the speed of the transmission train and the work machine, and means connected to and operable only during and in response to every change in position of the control means for positively moving said normally stationary reactor element in a direction to provide an accelerating kick of the work machine in the same direction as the change in speed of the power source resulting from the change in position of the control means,

8. In a turret, a power source, a work machine, a power transmission train operatively connecting said power source and said work machine for transmitting power from the source to the machine, said train including a transmitting element connected to the work machine, a normally stationary reactor element against which said transmitting element reacts while transmitting power, control means for changing the speed of said power source to proportionately change the speed of the transmission train and the work machine, and means connected to and operable only during and in response to every change in position ofthe control means for positively moving said normally stationary reactor element in a directionto provide an accelerating kick of the work machine in the same direction as the change in speed of the power source resulting from the change in position of the control means.

9. In combination, a power source, a work machine, a transmission train connecting the power source and the machine for transmitting power to the machine, said transmission train including three mutually reacting elements, one of said three elements being a normally stationary element, control means including a manually operable handle for changing in accordance with the amount of movement of the handle the speed of the power source to provide a proportionate change in speed of the work machine, and mechanical connection means between said handle and said normally stationary element for positively moving said stationary element to provide an accelerating kick of the work machine only during and in accordance with the movement of said handle.

KENDALL CLARK.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,201,105 Saqui et al. Oct. l0, 1916 1,270,028 Henderson June 18, 1918 1,702,627 Bronander Feb. 19, 1929 1,727,232 Farrell Sept. 3, 1929 1,803,064 Karnes Apr. 28, 1931 2,098,352 Muller Nov. 9, 1937 2,164,818 Heyer et al. July 4, 1939 2,179,933 Heyer Nov. 14, 1939 2,230,149 Weddington Jan. 28, 1941 2,268,113 Fidelman Dec. 30, 1941 2,282,742 Poysa May 12, 1942 2,300,343 Clay Oct. 27, 1942 2,344,352 Graham Mar. 14, 1944 2,363,523 Greenblatt et al. Nov. 28, 1944 2,366,072 Tucker Dec. 26, 1944 2,373,990 Barnhart Apr. 17, 1945 2,378,050 Vaughan June 12, 1945 2,382,777 Dahlberg Aug. 14, 1945 2,385,348 Chafee Sept. 25, 1945 2,399,200 Brown Apr. 30, 1946 2,434,653 Holschuh et a1. Jan. 20, 1948 2,436,582 Lear Feb. 24, 1948 FOREIGN PATENTS Number Country Date 350,955 Great Britain June 11, 1931 436,071 Great Britain June 4, 1935 800,959 France May 11, 1936 

